Folks,

Need advice on an unfixable problem:

Original owner, 5-cyl, non-turbo, 85,000 mi, FWD, wagon.

Worked on by our trusted mechanic.

No engine or transmission codes have ever appeared.

PROBLEM DESCRIPTION:
All events occurred while going up slight inclines on surface streets or freeways.
0746 (Time): Engine start. A/C off. 59F.
0748: 2000 rpm, 20 mph. Slow acceleration in 2nd gear from stop sign and car hesitates slightly with loss of acceleration.
0752: Car water temp normal.
0809: 3000 rpm, 75 mph. As soon as a slight uphill section is reached, the car smission problem started to appear. On slight incline or when on freeway: carstarts to surge a little back and forth (as if its slipping the clutch or power is being added and lost).
0811: 2100-2500 rpm, 2nd gear, onramp. Car surges a little in 2nd gear.
0813: 3100 rpm, 77 mph. While on uphill section, the car shudders slightly and surges back and forth a little.
0814: Same again.
0815: Same again.
0820: Same again.
0822: Depressed accelerator while on uphill section to maintain speed and car car shudders slightly and surges back and forth a little.
0827: 2000 rpm, 20 mph. Accelerating in 2nd gear, car hestitates, surges back and forth moderately, rpm goes from 2300 to 4000 rpm immediately, and then drops into 3rd gear at about 2000 rpm at 35 mph.
0830: In one second: Rpm goes up from 3100 to 4100, car slows, rpm return to 3100 with a clunk, as if trans went from neutral to drive.

Mechanic says it's a bad trans.

1st problems appeared early 2007 and got worse over six months to the poitn we needed to fix it. Trans replaced Sep 2007. 1st week everything OK, but then the hesitation problem reappeared and after a few weeks all appeared problems and were almost identical to the 1st transmission's. Mechanic reset trans computer back to original settings. Problems went away for about a week and then gradually returned. 2nd trans replaced Nov 2007. 3rd trans has exactly same scenario as 2nd trans. Currently, with 3rd trans in car for the 10 days now, having hesitations which are occurring more often day by day.

It seems to me its not a trans problem but something that controls the trans. Trans computer? With no codes, my mechanic does not want to change it. Anything else??

Hope you have a good suggestion because otherwise, it's off to the dealer.

Thanx much

GRG